Various systems of modular shelving have been proposed. Generally, such systems include upright supports, shelf supports or brackets, and shelves that are supported by the brackets. Previous systems may be undesirable due to stability, installation, and/or assembly issues. For example, many systems may be unstable, such as when moved or unintentionally pushed from the front or sides. Many systems may also require the upright supports to be mounted to a wall, requiring permanent alteration to the shelf location and often requiring various tools for assembly. In configurations using cantilever brackets attached to the front of the supports, the shelves may be unsteady such as when the bracket is unintentionally moved. In some cases, additional support is given to the shelf unit by providing bases or other supports at the bottom of the upright supports. This may be undesirable, since it may prevent one unit from being placed adjacent to another, increasing the amount of space required for multiple units.